movement in sports

Diagram

List of Apparatus

• Bores

• Clamp stand

• String

• Clipped roller

• Masses ranging in weight such as 10g, 20g 50g and 100g

• Ruler with hooked nails put into every 5cm

Preliminary Work

I carried out some preliminary work before the experiment on the basis that it would help me decide the weight I would use. I used three different amounts of weight, which started, from 120g, 140g and 160g. After carrying out the tests, I had decided to use 140g. Below are the results of the preliminary work:

By looking at the results, this shows me that overall 140g was the median experiment, as it did not take the most effort or the least. This is the reason why I have chosen to go ahead with 140g as my actual load weight in the proper experiment. The preliminary work served another purpose as well which was determining how to make the best use of the equipment. After looking at different ideas, it was decided that the clamp would be ideal if it was attached to the stool rather the edge of the table as this would allow the masses to move more freely.

Variables

In this experiment, I will be changing one variable. This is the position of the string, that I will be increasing every 5cm until it reaches 45cm, which gives it nine distances.

However, there are few variables that I will keep the same. The first one is measuring the effort required to lift the load and then find out the mechanical advantage and velocity ratio used. The second one is keeping the weight of the load at 140g.

Fair Test

In order to make this a fair test, I will have to control various factors of the experiment. One factor would be the position of the model arm. I will have to control it by making sure it is screwed onto the metal and remains at the bottom. In addition, I will attach the whole model to a chair, as it is better suited rather than attaching it to the edge of the table, as it is not an ideal position to carry out the experiment.

Another factor I shall control is the number of times we carry out the test. I make sure that it is carried out no less than 3 times as this will allow us to gain the most accurate results as possible. To expand on the accuracy of the experiment, I will put the masses on a mass holder and take measurements once the arm has reached the top. However, this may be difficult as the masses are not to scale either way to 3 grams.

Risk Assessment

This risk assessment is not based on the actual experiment, as it does not contain any severe risks however; the apparatus being used has potential dangers if not used properly. These would be:

• The equipment being used should be correctly set up. By doing this, you can prevent any harm to yourselves and others.
• The weights used should be handled with care otherwise, it could cause damage to either yourselves or others if it falls on someone. It could also damage school property.
• To avoid dropping the weights, extra attention should be taken to check whether the hoops are tied on properly.
• Keep distance between yourselves and fellow classmates to allow a good working area for yourselves and others. This will limit the chances of someone getting hurt.
• Handle equipment with extra care to prevent any damage to the equipment itself and other school property.
• Make sure clamp stand is properly secured to the chair or table otherwise could cause serious damage to others or property.

Prediction

I predict that the mechanical advantage will increase, as the position of the ruler will move away from the pivot and the velocity ratio will decrease.

Method

• Using the apparatus stated above, set up the clamp stand positioning the boss and clamp at the top.
• Put the clipped roller halfway on the clamp bar.
• Using another boss, attach it to the clamp stand and connect it through the meter ruler.
• Collect a piece of string and tie a hoop on both ends, making sure it is secure.
• Put the string through the clipped roller and then attach it on the meter ruler with the hooks.
• Whilst one end of the string is attached to the ruler, using the other end, attach a mass to it and keep adding more mass on until it lifts up the ruler.
• Keep repeating this process while moving the string at different distances on the ruler.
• Record the results.

Result

Analysis of Graphs

The graph shows that as the distance to effort is increased, the velocity ratio decreases.

The graph shows that as the distance to effort increases, the mechanical advantage therefore proving my prediction right.

Evaluation

Looking at my results and graphs, I felt that the experiment went exceptionally well however there was basis for improvements. During the experiment, errors that had occurred were the limited use of equipment. To elaborate, there was not enough equipment for the whole class therefore some pupils had to wait their turns and equipment kept exchanging hands on a regular basis. The effect this had on the experiment was it would have caused the distance to change. Another error that had occurred was the rulers. They had nails inserted into them at each cm but were not placed accurately therefore had to keep changing rulers which prolonged the experiment. Finally, the weights were not as accurate as they could have been which would have had a knock on effect on the results.

In order to make the equipment more accurate, I would make sure there are accurate weights, which would have given me better results. In addition, I would have more equipment therefore; the quickness of the experiment is still preserved. Most importantly, I would make sure all the equipment is accurate which provides better results.

To test the work further, I would conduct an experiment with different shapes to determine whether they have an effect on the results.

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